Traditional techniques for quantifying and detecting the presence of proteins include gel electrophoresis, Western blotting, ELISA based immunoabsorbent assays and protein microarrays. Each of these methods are cumbersome and not amenable to high-throughput use. These traditional methods also suffer limitations in detection sensitivity and specificity. Provided herein is a nucleic acid tag and a new, highly sensitive and selective method of protein detection using the nucleic acid tags.